Polyphenylene ether resins are widely known as the resin having high heat resistance, mechanical properties, flame retardancy, and electrical properties. The polyphenylene ether resins having such properties are used in broad ranges of applications such as automobile parts, electrical and electronic parts, business apparatuses, industrial products, and construction materials, and have recently received attention as a resin material for forming a sealed type secondary battery container. The sealed type secondary battery container is known as a nickel-hydrogen battery or the like, and widely used as power sources for vehicles such as automobiles and a variety of electrical products and industrial apparatuses. The demand for the sealed type secondary battery container has been increasing. The performance of the battery main body is improved with this increasing demand, and the battery container itself has been reduced in size and weight and the electric capacity of the battery has been increased.
In the related art, as the resin for forming a secondary battery container (resin for a secondary battery container), ABS resins and a modified polyphenylene ether resins are used from the viewpoint of molding properties and heat resistance, for example. Unfortunately, these resins have poor anti-hydrogen permeability, and cause reduction in the performance of the battery. Moreover, the ABS resins and the modified polyphenylene ether resins have poor resistance against chemicals. For this reason, these resins have insufficient resistance against chemicals such as automobile oils, and cannot be used for the secondary battery container for automobiles or the like for a long time.
To solve these problems, for example, Patent Document 1 discloses a sealed type secondary battery container comprising a resin composition containing a crystalline polyolefin resin and a polyphenylene ether-based resin. Patent Document 2 discloses a sealed type secondary battery container using a polymer alloy comprising a polyphenylene ether resin and a polyolefin resin. Patent Document 3 discloses a resin composition in which a polyphenylene ether resin is dispersed in a specific form in a crystalline polypropylene resin. Patent Documents 4 to 6 each disclose a resin composition comprising a polyphenylene ether-based resin and a crystalline polypropylene having a specific structure, the resin composition being usable as a container for a sealed type secondary battery. Patent Document 7 discloses a composition in which reduction in flow marks are tried. Patent Document 8 discloses a composition in which improvement in molding fluidity is tried.